This invention relates to a beverage dispense system in which a chilled beverage is presented to the consumer. It is particularly applicable to beverages such as beer or lager.
Conventional beer/lager cooling systems typically have a bulk beverage supply located at a separate location (called a cellar room) from the bar counter and the beverage is chilled in the cellar by being passed through an ice bank cooler to a temperature just below its ultimate dispense temperature. The chilled beverage is then pumped from the cellar room to the bar within an insulated python.
If one wishes to dispense the beverage at very cold temperatures e.g. below 0xc2x0 C., such a system has problems. In particular, one has to chill the beverage in the cellar room to an even lower temperature. Whilst one can utilize glycol mixtures in the ice bank cooler instead of water to obtain lower beverage temperatures, the lower the required beverage temperature the greater the risk that it will freeze solid in the cooler or the python during periods when the beverage is not being dispensed. It will then be impossible to operate the dispense system when the next drink is required to be dispensed.
It is an object of the invention to provide a system which is capable of successfully dispensing a chilled beverage from a bulk supply to a temperature close to the freezing point of the beverage.
Accordingly in one aspect the invention provides a chilled beverage dispense system including a beverage recirculation loop and a glycol recirculation loop, a first chiller to cool the beverage and a second chiller to cool the glycol, a heat exchanger through which the cooled beverage and the cooled glycol are passed to further cool the beverage and a dispense valve located in the beverage recirculation loop downstream of the heat exchanger, the glycol recirculation loop including a bypass valve upstream of the heat exchanger, whereby in a standby, non-dispense mode the glycol bypasses the heat exchanger and when a beverage dispense is required, the glycol is diverted through the heat exchanger.
In another aspect the invention provides a method of dispensing a cooled beverage in which the beverage is passed in a recirculation loop through a first chiller to cool it and then through a heat exchanger and then via a dispense head to return to the first chiller, a glycol coolant is passed in a recirculation loop through a second chiller to a bypass valve to avoid passing through the heat exchanger when beverage is not being dispensed and then back to the second chiller, the bypass valve being actuated when a dispense is required whereby the glycol coolant passes through the heat exchanger to further cool the beverage before it is dispensed.
It will be appreciated, therefore, that the beverage can be maintained in its first cooled condition, e.g. from 0.5xc2x0 to 1.5xc2x0 C., typically 1xc2x0 C., in the standby mode by means of recirculation through its first chiller but that when dispense is required it is further cooled by heat exchange within the heat exchanger with the colder glycol that is now diverted from its bypass mode to flow through the heat exchanger. The glycol may be maintained at, e.g. from xe2x88x928.5xc2x0 to xe2x88x929.5xc2x0 C., typically xe2x88x929xc2x0 C., to give a second cooling to the beverage which may then be dispensed at e.g. from xe2x88x924xc2x0 to xe2x88x925xc2x0 C., typically xe2x88x924.5xc2x0 C. It will be appreciated that these ranges will vary depending on the beverage to be dispensed.
The heat exchanger may be of any convenient plate, tube or other construction.
During standby mode, glycol remaining in the heat exchanger will, of course, warm up from its chilled temperature but will be maintained at about the temperature of the recirculating beverage.
If the heat exchanger is located close to the dispense valve so that the amount of beverage at any point in time from the heat exchanger to the dispense valve is small relative to the amount to be dispensed, it may be possible to arrange a control system that commences dispense at the same time as operating the bypass valve to divert the glycol through the heat exchanger. However, it is preferred that a control system be used that, on a dispense being actuated, first operates the bypass valve to further cool the beverage and then, after a delay, opens the dispense valve. The delay may be a predetermined time or may be determined by a temperature sensor for the beverage positioned between the heat exchanger and the dispense valve. In this latter embodiment, the dispense valve will only open once the temperature sensor indicates to the control system that the required dispense temperature has been reached.
The glycol coolant used may be pure glycol but will usually be a water/glycol mixture, e.g. of proportions from 25:75 to 50:50, depending on the degree of cooling required.
In a preferred embodiment a water recirculation loop is included in the system in order to provide a spray of chilled water onto a glass or other receptacle into which the beverage is to be dispensed. The water may conveniently be chilled in the same first chiller used for the beverage recirculation loop. This first chiller may be a single ice bank cooler of conventional design with a portion of the beverage recirculation loop and of the water recirculation loop immersed in water/ice within the cooler.
A water dispense valve is provided in the water recirculation loop and controlled quantities of chilled water at from, e.g. 0.5xc2x0 to 1.5xc2x0 C., may be sprayed onto the beverage receptacle in response to signals from the beverage dispense control system. The receptacle may be sprayed before, during and/or after beverage is dispensed into it.
The invention provides a system in which cooler than usual beverage can be dispensed safely and without risk of freezing. A conventional ice bank cooler can be used for the initial cooling (first chiller) and to maintain the cooled effect between dispenses and the heat exchanger is used to provide the extra cooling when required for a dispense. Between dispenses the heat exchanger is bypassed by the recirculating glycol coolant and the system xe2x80x9cidlesxe2x80x9d with the beverage at the temperature achieved by the first chiller.
The dispense valve can be permanently chilled in the beverage recirculation loop and so does not harmfully affect dispense temperature after standing unused.